A mathematical model of blood flow through microvascular networks has beendeveloped; it accounts for the non-linear flow characteristics of blood and the non-uniform distribution of cells in each vessel, as well as the disproportionate partitioning of cells during blood flow through vascular bifurcations. The computational methodology of the model was validated, and the model was used to show the importance of diameter variability and to predict temporal variations in local flow parameters in several mesenteric microvascular networks. In the next phase of this simulation study the model will be used to study several categories of problems: a) continued comparison between in-vivo data and model simulation parameter values, with the main intent being to develop hemodynamic and anatomical relationships in the computer model which are essential for more realistic representation of the real microvascular network blood flow, b) incorporation of a more realistic representation of microvessel structure-function characteristics into the simulation model, comparison of simulations with real in-vivo data, and use of the successful model version to study the roles and impacts of the various control mechanisms on blood flow control, c) study of the chaotic nature of blood flow in microvascular networks, as a function of spatial location in the network, of hemodynamic variables, etc. The results from this study will be used to determine blood flow control mechanisms at the microvascular network level and oxygen and nutrient distribution to the tissue.